Correction and Maintenance of Cervical Alignment: 3-Level ACDF Versus Corpectomy-ACDF "Hybrid" Procedures.

STUDY DESIGN: Longitudinal observational comparative cohorts. OBJECTIVE: The objective of this study is to compare 3 and 12-month radiographic sagittal parameters and patient-reported outcomes (PROs) in patients who underwent 3-level ACDF or a hybrid procedure. SUMMARY OF BACKGROUND DATA: Anterior Cervical Discectomy and Fusion (ACDF), Anterior Cervical Corpectomy and Fusion (ACCF), and hybrids (combination ACCF-ACDF) are common procedures used to treat symptomatic cervical spondylosis. Although there is a relative abundance of literature comparing 1-level ACCF versus 2-level ACDF and 2-level ACCF versus 3-level ACDF, detailed comparisons of 3-level ACDF versus hybrid procedures have not been extensively addressed. METHODS: Patients who underwent a 3-Level ACDF (3L-ACDF, N=47) or 1-Level Corpectomy/1-Level ACDF (Hybrid, N=52) with at least a 12-month post-op data available were identified. Standard demographic, surgical and PROs were collected in addition to preoperative and postoperative radiographic data, including C2 plumb line (C2PL), C2-C7 lordosis (CL), segmental lordosis (SL), and T1 slope (T1S). RESULTS: The 2 cohorts were similar in terms of demographics. At 3 months post-op, CL (9.04° vs. -2.12°, P =0.00) and SL (6.06° vs. -2.26°, P =0.003) were significantly greater in the 3L-ACDF group versus the HYBRID group. This significant difference was maintained at 12 months postoperative for CL [(6.62° vs. -0.60°, P =0.015) but not for SL (2.36° vs. -1.09°, P =0.199)]. There were no differences in PROs between the 2 groups before surgery, at 3 months postoperative or 12 months postoperative. Seven patients required revision surgery in the 1-year study period (1 in the 3L-ACDF, and 6 in the Hybrid P <0.001). CONCLUSIONS: Three level ACDF resulted in greater C2-C7 lordosis and segmental lordosis postoperatively, which was maintained at 1 year for cervical lordosis. While PROs were similar between the groups, patients with hybrid instrumentation required significantly more revision surgeries than those treated with 3-level ACDF.

Evaluation of bone mineral density after instrumented lumbar fusion with computed tomography.

BACKGROUND CONTEXT: Computed tomography (CT) measurement of Hounsfield Units (HU) has been described as a tool for assessing BMD. For surgeons considering a revision lumbar fusion, knowledge of the BMD of the UIV is of value for surgical planning. However, the presence of metal artifact from instrumentation presents a potential confounder, and prior studies have not validated measurements of HU in this setting. PURPOSE: To determine if HU can be measured reliably at the supra-adjacent and upper instrumented levels of a lumbar fusion. STUDY DESIGN: Retrospective observational cohort PATIENT SAMPLE: Consecutive series of patients who had lumbar CT scans after an instrumented posterior lumbar fusion. OUTCOME MEASURES: Hounsfield Units at the upper instrumented vertebra and levels proximal. METHODS: We analysed pre- and postoperative CT scans of 50 patients who underwent L2 and distal instrumented lumbar fusion whose scans were no greater than 1 year apart, obtaining HU measurements of analogous axial cuts at the upper instrumented level (immediately caudal to the halo of the pedicle screw), as well as additional control levels above the construct. RESULTS: The HU at the pre-and postoperative UIV exhibited a strong correlation (r=0.917, p<.001), as did one (r=0.887, p<.001) and two (r=0.853, p<.001) levels above the UIV. There were significant but predictable reductions in the postoperative HU compared to preoperative at one (-9.0±26.2) and two (-12.2±30.2) levels above the UIV, as well as T12 (-13.9±42.2). There was no significant difference in HU at the UIV (4.6±34.1). CONCLUSIONS: Postoperative HU at the UIV was strongly correlated with and not significantly different from the preoperative HU. Although the HU in the vertebrae proximal to the UIV were slightly lower postoperatively, this change was predictable using a correction factor.

A track record of diversity: Medical schools ranked by successful black applicants to orthopaedic residencies.

BACKGROUND: Orthopaedic surgery is the least diverse surgical subspecialty in medicine. However, to date, there is no literature that shows which medical schools have successfully contributed to improving orthopaedic surgeon diversity. OBJECTIVE: The purpose of this study is to identify the top U.S. medical schools that have successfully matched black applicants into orthopaedic surgery residencies and juxtapose this ranking to the current top medical schools as ranked by the U.S. News and World Report (USNWR). METHODS: The J. Robert Gladden Orthopaedic Society (JRGOS) database was queried for all orthopaedic surgeons, fellows, and residents who identified as black or multi-racial with black being one of the included races, yielding 938 physicians, of which 672 met our inclusion criteria. From this list, a ranking of the top 20 medical schools was generated. RESULTS: The top five medical schools ranked in the JRGOS database are Howard University College of Medicine (HUCOM), Meharry Medical College, Harvard Medical School (HMS), the University of Pennsylvania, and Morehouse School of Medicine (MSM). In addition, 10 (50%) of the medical schools ranked in the top 20 by the JRGOS database were also ranked by the USNWR. When ranking medical schools for black female applicants, HUCOM, MSM, HMS are the top three programs. Lastly, a ranking by region identified that the northeast contained the highest number of ranked medical schools. CONCLUSION: There are both historically black and non-historically black medical schools which have a proven track record of producing a significant number of future black orthopaedic surgery residents.

When does CT myelography add value beyond MRI for lumbar degenerative disease?

BACKGROUND CONTEXT: In patients with lumbar spinal stenosis, it is crucial for clinicians to identify all symptomatic levels. Prior studies have demonstrated that CT myelography has a greater sensitivity in revealing stenosis (94.4%) compared to MRI (75.9%). However, this is an invasive test that should be used judiciously. No study has identified subgroups of patients that do or do not benefit from this additional invasive testing. PURPOSE: The objective of this study was to identify subgroups of patients with lumbar stenosis for whom CT myelogram could be expected to provide additional information following an MRI scan. STUDY DESIGN: Retrospective chart review. PATIENT SAMPLE: Consecutive series of patients with lumbar degenerative disease seen at a single multisurgeon tertiary spine center. OUTCOME MEASURES: Degree of stenosis on MRI or CT myelo. METHODS: Medical records were reviewed to collect standard demographic and surgical data and patient diagnoses. MRI and CT myelo obtained within 6 months of each other in patients >45 years old with a diagnosis of central stenosis, spondylolisthesis or degenerative scoliosis were reviewed. Each lumbar level was recorded as mild, moderate, or severe based on the radiologist's report. Fisher exact test was performed with change in recorded severity of stenosis from MRI to CT myelo as the primary outcome of interest. RESULTS: Of 269 patients, 207 (80%) had at least one level of moderate or severe central stenosis on MRI and 62 had mild or no stenosis on MRI. Of the 207, 139 (67%) had multilevel stenosis and 68 (33%) had single level stenosis. CT myelo identified a greater proportion of additional stenotic levels in patients with multilevel stenosis (80/139, 58%) compared to patients with single-level stenosis (27/68, 40%, p=.018). In 62 patients with a clinical diagnosis of lumbar stenosis but no moderate to severe stenosis on MRI, CT myelogram identified three additional stenotic levels (3/65, 5%, p=.836). CONCLUSIONS: CT myelography is not as useful in providing additional information in patients with no stenosis or single level stenosis as compared to patients with multilevel stenosis.

Quantitative Romberg using a force plate: an objective measure for cervical myelopathy.

BACKGROUND CONTEXT: Surgical decision making for cervical spondylotic myelopathy (CSM) relies on evaluation of symptoms and physical examination. The Romberg test is a clinical exam used to identify balance issues with CSM. However, the Romberg test has a subjective interpretation and has a binary (positive or negative) result. PURPOSE: This study aims to compare force plate pressure readings during a standard Romberg test in patients with CSM to age-matched normal healthy volunteers. STUDY DESIGN/SETTING: Prospective cross sectional observational comparative cohort from a single multi-surgeon spine center. PATIENT SAMPLE: Patients who were clinically diagnosed with CSM were compared to age-matched healthy volunteers without a clinical history of spine pathology. OUTCOME MEASURES: Quantitative Romberg Force Plate Measurements METHODS: Patients with CSM requiring surgery and healthy normal volunteers were asked to perform the Romberg test while on a force plate measuring the center of pressure (COP): standing up straight with arms extended for 30 seconds with eyes open, followed by 30 seconds with eyes closed. The change for total sway area, sway frequency and sway speed with eyes closed and eyes open were calculated and compared between patients with CSM and healthy volunteers. RESULTS: Thirty-four CSM patients were age-matched to 34 healthy volunteers. There was a larger change in quantitative Romberg measurements with eyes open versus eyes closed in CSM patients compared to normal volunteers for maximum lateral movement (10.79 cm vs. 0.94 cm, p=.003), maximum anterior-posterior movement (15.06 cm vs. 10.00 cm p=.201), total lateral CoP movement (89.82cm vs. 18.71cm, p=.007), total AP CoP movement (154.68 cm vs. 87.47 cm, p=.601), total CoP trace movement (199.79 cm vs. 88.44 cm, p=.014), sway area (284.74 cm2 vs. 57.76 cm2, p=.006), and average speed (7.00 cm/s vs. 2.91 cm/s, p=.006). DISCUSSION: Poor standing balance can be quantified in patients with CSM. Quantifying standing balance in patients with CSM shows significantly worse objective measures than age-matched healthy volunteers. The Romberg test on a force plate may help diagnose and evaluate patients with CSM, guide patient management and potentially grade the severity of spinal pathology. Further studies are needed to determine its utility in monitoring disease progression and measure treatment effectiveness.

Improvement of coronal alignment in fractional low lumbar curves with the use of anterior interbody devices.

STUDY DESIGN: Retrospective chart review. OBJECTIVES: To determine if the addition of an anterior lumbar interbody fusion (ALIF) improves the fractional curve in adult spinal deformity correction when compared to posterior surgery alone. ALIF is commonly advocated to improve lordosis and fusion in adult deformity surgery. Improved fractional curve correction may help level the pelvis and minimize proximal malalignment. METHODS: Patients undergoing thoracolumbar fusion to the pelvis with S2AI screws for deformity were identified and stratified into patients who had an ALIF as part of their deformity correction procedure (ALIF + PSF), and those who had a posterior approach alone. The posterior approach (PSF) includes patients who had a posterolateral fusion with or without a transforaminal lumbar interbody fusion (TLIF). Radiographic parameters measured included pre-op and post-op fractional coronal curve Cobb angle, lumbar lordosis, pelvic tilt, pelvic incidence and sacral slope, major Cobb angle, coronal and sagittal SVA. RESULTS: There were 31 cases in the ALIF + PSF group and 28 in the PSF group. Baseline demographic characteristics of the two groups were similar. Mean pre-op fractional coronal Cobb (18.3° vs 13.4°, p = 0.027) was larger in the ALIF + PSF group, whereas lumbar lordosis (31.0° vs 33.6°, p = 0.487) and pelvic parameters were similar between the two groups. Post-op lumbar lordosis was similar (48.2° vs 43.0°, p = 0.092). Greater fractional coronal curve correction was achieved in the ALIF + PSF group (67%) compared to the PSF group (36%) with a smaller post-op fractional coronal curve in the ALIF + PSF group (6.1°) compared to the PSF group (8.6°, p = 0.053). CONCLUSION: There is a greater correction of the fractional curve in the ALIF + PSF group compared with the PSF group. While this may not be the primary indication for ALIF, it is a benefit which may facilitate overall deformity correction and leveling of the pelvis.

Is There Additional Value to Flexion-Extension Radiographs for Degenerative Spondylolisthesis?

STUDY DESIGN: Multicenter retrospective study. OBJECTIVE: Flexion-extension radiographs are frequently used to assess motion in patients with degenerative spondylolisthesis. However, they expose patients to additional radiation and increase cost. The aim of this study is to determine if flexion-extension radiographs provide additional information not seen on upright neutral radiographs and supine magnetic resonance imaging (MRI) that may guide surgical decision making. SUMMARY OF BACKGROUND DATA: Supine MRI and upright neutral radiographs are routinely performed in patients with degenerative spondylolisthesis. It is unclear whether additional flexion-extension views play a significant role in surgical planning for this patient population. METHODS: From the Quality Outcomes Database, patients who had surgery for grade 1 degenerative spondylolisthesis were identified. Magnitude of slip on pre-op supine MRI, upright neutral, flexion, and extension radiographs were measured. Additional motion was defined as 3 mm or more slip difference between radiographs. For the purpose of this analysis, patients with a slip of 7 mm or more on upright neutral radiographs were assumed to require a fusion. RESULTS: A total of 191 patients were identified. Mean age was 61.6 years (114 females, 60%). Only 31 patients (16%) had additional motion on flexion-extension views not seen on upright neutral x-rays versus supine MRI. Of these 31 patients, 19 had slips less than 7 mm on upright x-ray, generating equipoise for fusion. CONCLUSION: Flexion-extension radiographs may play a limited role in management of degenerative spondylolisthesis. The subset of patients for which flexion-extension views were most likely to provide value were patients with smaller slips (<7 mm) with no evidence of motion on standing radiographs versus MRI. In 90% of spondylolisthesis cases, information used for surgical planning may be ascertained by comparing motion between supine MRI and upright lateral radiographs.Level of Evidence: 3.